Our best-selling Brighton Base Layer features an engineered Merino mesh that’s more open around your core, with a closed knit on the sleeves for a bit more warmth in your extremities. We designed it specifically as a training base layer to be worn under a mid-layer or a jacket, but its seamless construction gives it a comfortable, flattering fit that’s not too tight to wear all by itself. EDITOR'S NOTES "Soft, breathable, and odor-resistant, the Brighton Base Layer is ideal for cold runs when you need to layer, and can also be worn on its own." —Runner's World